24-NA-078

Bulletin No.: 24-NA-078
Service Bulletin
Date: April, 2024
TECHNICAL
Subject:
Brand:
Chevrolet
GMC
Intermittent Grinding and/or Growling Noise from Under the Vehicle with
Engine Running
Model:
Model Year:
from
to
2023
2024
VIN:
from
Engine:
Transmission:
L3B, L2R
N8R, MFC
to
Colorado
Silverado 1500
Canyon
Involved Region or Country
North America, Russia, Middle East, Israel, Chile (West), Colombia (West), Ecuador
(West), Venezuela (West), Japan, Thailand (ASEAN), Singapore, Other Africa
Condition
Some customers may comment on hearing an intermittent grinding or growling noise
from under the vehicle with engine running.
Cause
This condition may be caused by the engine starter (Bendix) hanging up and contacting
flywheel while engine is running.
- Technician may be able to duplicate noise and track it to the bell housing area of the
transmission. Noise will be intermittent and erratic.
Important: Do Not replace the transmission for this intermittent noise in the bell housing
area.
Correction
Technicians can diagnose noise by placing a stethoscope or other listening device on
starter motor when concern is happening.
- If the noise has been verified to be coming from the bellhousing area, replace the
starter.
Important: Service agents must comply with all
International, Federal, State, Provincial, and/or
Local laws applicable to the activities it performs
under this bulletin, including but not limited to
handling, deploying, preparing, classifying,
packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict
between the procedures set forth in this bulletin
and the laws that apply to your dealership, you
must follow those applicable laws.
Parts Information
Note: Only select the parts that coincide with the repair
performed. Replace the part with the P/N outlined in
the Electronic Parts Catalog (EPC) in accordance with
the vehicle VIN.
Causal
Part
Description
Part Number
Qty
X
STARTER
12730103
1
Service Procedure
Warranty Information
Refer to Starter Replacement.
For vehicles repaired under warranty, use:
Copyright 2024 General Motors. All Rights Reserved.
Page 2
April, 2024
Bulletin No.: 24-NA-078
Labor Operation
Description
Labor Time
4041250
Starter Replacement
Use the Published Labor
Operations Time
Version
1
Modified
Released April 24, 2024
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job
properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
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